For red, you can possibly rely on redirect spells, as mentioned in the Knowing How to Build a Commander Deck Will Require All Kinds of Removal section
Tune the Narrative Tune the Narrative is perfect
If neither door of a Room is unlocked, it's a Room enchantment with no name and no abilities
Again, this is a bit of a long shot, but Imps Mischief is a little too color-shifted for WotC to be all that eager to run it back
He does make your horses tanky while nerfing everyone else though, so I've had a lot of good luck trying him out
While this certainly makes Zanarkand, Ancient Metropolis a much more interesting addition to Chatterfang decks, it has a lot more far-reaching implications for Commander, many of which are seeing play already